This invention relates to milling or machining apparatus, and auxiliary equipment therefor, and is more specifically directed to a device that handles pallets on which are mounted workpieces that are to be positioned at a work station adjacent the milling or machining apparatus.
The invention is more particularly concerned with a device in which raw workpieces can be mounted on an upper surface of a pallet on the device, after which the device automatically positions the pallet and its workpiece or workpieces at the milling or machining work station, and brings out from the work station a similar pallet containing parts which have been suitably machined by an earlier operation. The latter pallet is brought to a cleaning or working station within the device where metal chips and other milling debris are washed and/or blown from the finished parts and from the pallet, after which the pallet is positioned so that an operator can remove the finished parts and replace them with fresh, unmachined workpieces.
It is the current practice for an operator to position workpieces by hand at a milling machine, or if a pallet is employed for carrying the workpieces, to position the pallet by hand at a work station beneath the head of the milling machine tool.
An automatic set-up system for providing palletized work to be machined by an automatic machine tool has been proposed in U.S. Pat. No. 4,543,970. In that system the pallet is conveyed to the machining device, and the pallet and work that is clamped to it are fed into a cleaner where debris and chips are washed from the pallet and the machined parts. This system is rather complex and elaborate and is not readily field installable or retrofittable onto existing machining equipment. The system cannot be made compactly enough to be positioned alongside a milling center or the like. Also, the setting table and cleaner are in separate units, and an elaborate conveyer system is required to carry the pallets among its various stations. In addition, no effort has been made to address the problem of misalignment which can occur if metal chips or debris work themselves between a pallet and the bed of the milling machine on which the pallet sits. This is a significant problem, as an error of less than one mil can be sufficient to require scrapping of an entire batch of machined parts.